Can Convolutional Neural Networks be applied in domains other than image recognition?
Yes, Convolutional Neural Networks(CNNs) can and have been applied to non-image problems. Arguably, any problem in which the location of a feature(s) is relevant can be attempted via CNNs. CNNs works under the assumption that points close to each other in the data share some correlations/relationship whist points further apart don't share as much information. So, theoretically, if you can phrase your problem so that it meets this requirement(s), it can be attempted by a convolutional neural network. Here are few applications of CNNss that are dont involve images: 


Speech recognition
Character-level Convolutional Networks for Text Classification
Text classification using CNNs
Natural Language Processing
Time Series Forecasting
Sentence modeling
I've used 1-D CNNs on spectral data. Here are some examples of CNNs applied to spectral data : 


Spectral Convolutional Neural Network for music classification
Convolutional neural network based classification for hyperspectral data